Psychrometer



P. G. MAGNER Feb. 1, 1938.

SYCHROMETER Filed Jan. 18, 1935 gnam/MO@ .Philip GMagner Patented Feb. 1, 1938 UNITED STATES PSYCHROMETER Philip G. Magner, Wabash,

Ind., assignor to Minneapolis-Honeywell Regulator Company, Minneapolis, Minn., a corporation of Delaware Application January 18, 1935, Serial No. 2,366

7 Claims.

This invention relates to psychrometers and a sock and wick construction therefor.

Conventional psychrometers as known today, having a wick secured to the lower end of the sock, do not correctly indicate the humidity, es-

pecially when the relative humidity is low. The vreasons for the inaccurate indications of these psychrometers are that the temperature of the water supplied to the wick, and consequently the 10 temperature of thewater lsupplied to the sock,

may be diierent from the true wet bulb temperature whereby the wet bulb indications may be inaccurate upwardly or downwardly, depending on whether the water temperature is higher or lower than the true wet bulb temperature; that the wick may not supply sulcient water to the sock to be evaporated thereon; and that there may not be a suflicient amount of-flow of air past the sock to cause suflicient evaporation.

It is an object of this invention, therefore, to provide a psychrometer that eleminates'the above causes for faulty indications. y

Inasmuch as it would be impractical to maintain the temperature of the supply of 'water the `same as the true wet bulb temperature, it is an object of thisfinvention to provide means whereby the temperature of the water supplied to the sock is maintained at, or extremely near the true wet bulb temperature regardless of the temperature of the water supply.

More specically, it is an object of this invention to provide means -for passing the air or gas, the relative humidity of which is to be measured, over the wick supplying water to the sock whereby the water in the wick as it isdelivered to the sock is at or extremely near to the wet bulb temperature. f

In order to secure adequate wetting of the sock at all times it is an object of this invention to provide a novel sockv and wiclrconstruction.

More specifically, an object of this invention is to'provide aunitary or integral sock and wick device wherein there will be a free flow of water from the wick portion to the sock portion vof the sock and wick device.

Further, in order to provide an adequate ilow of air past the sock and wick, it is an object of this may be accomplished by the provision of a partition.

Other objects and advantages will become apparent to those. skilled in the art by reference to the accompanying specification, claims, and 5 drawing, in which: A

Fig. 1 is a vertical sectional view through the psychrometer of this invention;

Fig.'2 is a perspective view of the integral or unitary sock and wick device forming a part of v10 this invention;I and Figs. 3 and 4 are perspective views of the unitary sock and wick device applied to the ther- Amometer of the psychrometer of this invention.

level of the water supply in the reservoir is a transverse plate I5 having an opening therein near the center -thereof in which is soldered a tube I6. V

The upper portion of the housing I0 is provided 30 with an opening I1 in which is placed a cover member I 8. The cover member I8 isjprovided with a vertically extending tubular portion I9- and an elbow portion 20 forming gas or air inlets and outlets, respectively, for the housing or cas- 35' ing I0. A wet bulb thermometer 23 and a dry bulb thermometer 24 are secured andclamped in a clamp member 2| by means of a wing nut 22 cooperating with a screw. The thermometers 23 and 24 are inserted in the inlet tubular por-V 40 tion I3 and are held in place by means of the clamp 2 I being inserted in slots 25 in the' tubu` lar portion I9. From this it is seen that the thermometers 23 and 24 are maintained directly in the path of the gas or air the relative 45 humidity of which is to be measured.

Secured to the wet bulb thermometer 23 are a'sock 26 and awick 21. AThe wick 2 1 .extends downwardly from the upper portion of the sock .26 through the tube IG into the water supply of constructing the unitary sock and wick device o f this invention is clear1y illustrated. lAn elongated piece of tubular sock material such as rayon tubing is used. Near one end of the tubular sock material an incision 30 is made, as shown in Fig.

2. 'I'he wet bulb thermometer 23 is insertedthrough this incision 30 into the sock material, as shown in Figs. 3 and 4, and the portion of the sock material surrounding the thermometer v23 forms a sock. The remaining and larger portion of the tubular sock material extends downwardly into the water supply to form a wick portion 21 for supplying water to the sock portion 26. The bottom of the sock portion remote from the incision 30 is preferably closed by means of a string or like means 29. The sock and wick are secured to the wet bulb thermometer 23 by means of a string or like means 28.

By constructing the' wick and sock in the above described manner an improved operation is obthe wick portion 21 is prevented since water may flow from the sock portion to the wick portion below the string 28.

Referring now to Fig. l, it is seen that the wick portion 21 extends downwardly from the upper end of the sock portion 26. By reason of this, the

air or gas, the relativehumidity of which is'to be measured, is passed over both the sock portion 26 and the wick portion 21.J If the water supply is warmer than the true wet bulb temperature, this warmer water, as it travels up the wick portion 21 by capillary action, is cooled by evaporation caused by the air or gas passingover the wick portion 21. This evaporation of water in the wick portion 21 causes cooling of the water therein to, or nearly to, the true wet bulb temperature so that water at the correct temperature is supplied to the sock portion 26 by the wick portion 21 regardless of the temperature of the water supply. This construction in effect.' causes a precooling of the water used for wetting the sock portion 26, whereby accurate indications of humidity may be obtained. y

Air or gas is drawn in through the inlet tube I9 of the casing I0 and out through the outlet elbow 20 by means of a fan 3| which is operated by a conventional motor 32. The motor 32 is mounted on a base 33 which is made integral with the casing or housing i6 by means of a web 3l. Also integral with the housingv l0 is a gas or air funnel 35 which confines the flow of air about the fan 3| -to increase the eiiiciency of operation thereof.

By reason of the tubular portion Is of the cover member I8 the air or gas, the humidity of which is to be measured, is conned for passage overv the sock portion 26 and the wick portion 21 which vincreases the evaporating actionin the sock portion 26 to give more accurate wet bulb indications.

From the above it is seen that I have invented a psychrometer of novel construction wherein the water supplied to the sock by the wick is brought been shown and described, it is obvious that many modifications may be apparent to one skilled in the art, and consequently this invention is to be limited only by the scope of the .appended claims.

I claim as my invention:

1. In a device of the class described, a casing adapted to contain a water supply therein at a lower portion thereof, a gas inlet and a gas outlet in saidcasing, means for passing a.v gas the relative humidity of which is to be measured. through said inlet, downwardly through said casing, and said outlet, a'thermometer extending in said inlet in the path of ilow of the gas. and a sockand wick secured to said thermometer, said wick extending substantially vertically from the upper end of said sock and downwardly into said water supply whereby the gas passes over said sock and said wick to bring the water supplied to said sock by said wick to substantially wet bulb temperature.

2. In a device of the class described, a casing adapted to contain a water supply therein in a lower portion thereof, a gas inlet and a gas outlet in said casing, means for passing a gas, the relative humidity oi.' which is to be measured, through said inlet, downwardly through said casing, and

said outlet, a thermometer extending in said inlet in the path'of ilow of the gas, a sock and wick secured to said thermometer, said wick extending substantially vertically from the upper end of said sock and downwardly into said water supply whereby the gas Apasses over said sock and said wick to bring the water supplied to said sock by said wick to :substantially wet bulb temperature, and a partition in said casing above said wat r supply having an opening therein through whic said wick extends whereby contact of the circulated gas with the water supply is prevented.

3. In combination, a sock and wick construction comprising an elongated piece of tubular sock material having an incision therein, a thermom- 1 eter extending through said incision into said sock material, the portion of said sockvma'teril surrounding said thermometer forming a sock and the remainder of sock material forming a wick,

l said doubled back relation to said sock portion.

4. In combination, a sockl and wick construction comprising an elongated piece of tubular sock material having an incision therein, a thermometer extending through said incision into said sock material, the portion of said sock material surrounding .said thermometer forming a sock and the ren'iainder of said sock material forming a wick, the wick portion of said sock material being doubled back on the sock portion thereof and secured thereto, means for closing the open end of said sock portion, and means for securing the sock portion to said thermometer.

- 5. In a device of the class described, a casing adapted to contain a water supply therein in a lower portion thereof, a gas inlet and a gas outlet for said casing in an upper portion thereof, means 75 inlet in the'path of flow of the gas and at an angle to the horizontal, a unitary sock and wick device secured to said thermometer by extending said thermometer through an incision in said unitary sock and wick device, said wick portion of said device extending from the upper end of said sock portion of said device ldownwardly into said watersupply whereby the gas passes over said sock and wick portions to bring the water supplied'to said sock portion by1 said wick portion` to the-horizontal, a unitary sock and wick device secured to said thermometer by extending said -thermometer through an incision in said unitary .tri

sock and wick device, said wick portion of said',i device extending fromthe upper end ofsaid sock v portion of said device downwardly into sai'd water'.v

supply whereby the gas passes over said sock and y, wick portions to bring the water supplied to said@ 5` sock portion by said wick portion to substantially wet bulb temperature, and a partition in said ca'sing above. said water supply having an opening -therein through which said wick portioxf extends a;

whereby evaporation of said water supply by the l0 circulated gas is substantially prevented.

7. In a device of the class described,a passage for the iowV of a gas, the relativehumldity of which is to .be measured, a thermometer in said i. passage, a-sock and wick secured to said ther- 15 mometer, and a supply of water foi' said wick spaced from said sock, said wick extending from the end of said sock farthest from said water into said water over a path through said gas passage, the closest point of the path to the inlet o f the 20 passage being the end oi the sock to which -the wick is attached, whereby the gas passes over rst the sock and the wick and then the wick alone.

PHILIP Aci. MAQNER. 25 

